The present invention relates to portable radio transceiver and cellular telephones in general, and particularly to arrangements designed to reduce the electromagnetic field strength to which the user of such radios and telephones is normally exposed to.
A radio transceiver transmits radio signals, in the form of electromagnetic radiation, at predetermined frequencies. It will be appreciated by those skilled in the art that such radiation may inflict biological alterations on living tissues. Serious questions have arisen regarding the safety of users exposed to the cellular telephone electromagnetic wave radiation. Therefore, there is an urgent need to provide means for protecting users of portable transceivers in general and cellular telephone, in particular, from allegedly harmful exposure to the electromagnetic wave radiation.
Reference is now made to FIG. 1, which is a schematic illustration of an electromagnetic field generated by an antenna of a conventional cellular phone 2, as is known in the art. Antenna 4, of conventional cellular telephone 2, produces electromagnetic wave radiation, which is generally represented by field lines 6. The dissipated radiation penetrates the head and other parts of the body of the user 8.
There are known examples in the prior art confronting the issue of exposure to electromagnetic radiation, especially concerning cellular telephones. For instance, U.S. Pat. No. 5,657,386 to Schawnke entitled xe2x80x9cElectromagnetic Shield for Cellular Telephonexe2x80x9d; U.S. Pat. No. 5,444,866 to Cykiert entitled xe2x80x9cDevice for Shielding a Cellular Telephone User from Electromagnetic Waveswxe2x80x9d; U.S. Pat. No. 5,335,366 to Daniels entitled xe2x80x9cRadiation Shielding Apparatus for a Radio Transmitting Devicexe2x80x9d; and, U.S. Pat. No. 5,338,896 to Danforth entitled xe2x80x9cShield Device for Cellular Phonesxe2x80x9d, teach such examples. These examples invariably employ a radiation shield in a specific form or made of a specific material. Such a shield is designed to be disposed between the transmitting antenna of the hand held telephone and the head of the user.
However, as shown in FIG. 1, shield 10 can block only a portion of the radiation, represented by space 12, that is delineated between perforated lines 14. Direct emission, directed outside spaces 12, still penetrate the body of the user. Therefore, the partial shielding of the radiation when the cellular telephone is used in proximity of the head, leaves significant radiation unblocked. Furthermore, the shield and the body of the user also blocks or absorbs part of the transmitting and receiving radiation. Hence, attenuating the intensity of the received or transmitted signal and reducing the quality of communication.
Furthermore, in some cellular telephones, the antenna is generally placed inside the hand-held telephone housing, and therefore the electromagnetic waves radiate through the hand of the user. If the antenna is shielded all around, and not only in direction of the head, the quality of transmission and receiving deteriorates considerably.
It is an object of the present invention to provide a novel antenna apparatus for protecting the user against electromagnetic radiation generated by the antenna of a portable radio or a cellular telephone. It is a further object of the present invention to provide a communication device, which is easy to use, and has a low manufacturing cost.
There is thus provided according to the invention a novel antenna apparatus for connecting to a personal radio transmitting device for reducing RF emissions to a user, including an antenna disposed above the head of the user, a shield disposed between the antenna and the head of the user, for blocking RF emissions from penetrating there through toward the user, and a communication interface, connected to the antenna, for communicating between the antenna apparatus and the radio transmitting device. The antenna apparatus may further comprise antenna support for supporting the antenna above the head of the user. According to one embodiment, the antenna support comprise a support rod suitable for mounting to the personal radio device, the antenna is mounted atop the support rod, the shield may be mounted atop the support rod below the antenna, and the shield may be is substantially extended sideways.
According to another preferable embodiment the antenna is mounted on the shield. In accordance with yet another embodiment the antenna apparatus further includes shield support for supporting the shield between the head of the user and the antenna. The shield support may comprise any of the list consisting of a headset, a hat, a helmet, a harness, a hairpin, a hairpiece, a spectacle frame, and a visor. The antenna may be shaped as a rod, a pyramid, a cone, a curved plane, or a flat plane. The shield may be substantially convex, concave, or flat. The shield may also comprise an integral part of a helmet, a hat, a cap or a yarmulke.
The communication interface may comprise a wired or a wireless communication between the antenna apparatus and the radio-transmitting device. Wireless communication may comprise infrared, RF, or ultra-sound communication.
The antenna apparatus may further comprise a radio communication component, connected to the antenna, for transmitting or reception of radio transmissions conducted via the antenna. Preferably, the communication component is disposed adjacent to the antenna. Further preferably, the antenna apparatus further includes a power source for supplying power to the radio communication component and preferably disposed adjacent thereto. The radio communication component may comprise a transmitter, a receiver or a transceiver. Still, further preferably, the antenna apparatus further includes a processor, connected to the radio communication component and to the communication interface, for controlling the radio communication component, the processor being preferably disposed adjacent to the communication component.
In accordance with yet another preferable embodiment of the invention, the antenna apparatus may further comprise user interface in communication with the processor. The user interface may optionally comprise audio interface, visual interface, tactile interface, or any combination thereof. The visual interface may comprise a display screen. The tactile interface may comprise a keypad or a touch-screen. The audio interface may comprise a microphone or an earphone or both. Either wired or wireless communication connects the user interface to the processor. The wireless communication may comprise infrared, RF, or ultra-sound communication.
In accordance with yet a further embodiment of the invention, the antenna apparatus may further comprise a communication component, a power supply for the communication component, a processor for controlling the communication component, and user interface, all of which are disposed in a hand-held housing designed to be immediately adjacent to the head of the user while in operation.
Still, according to a further embodiment of the invention, the antenna apparatus further includes visual indication, for indicating to people in the vicinity of the user, the operational state of the communication device, namelyxe2x80x94the being of the antenna apparatus in use, in standby mode or turned off.
According to another feature of the invention there is provided a personal communication device including a transmitter, a processor, connected to the transmitter, for controlling the transmitter, an antenna, connected to the transmitter, disposed above the head of the user, a shield disposed between the antenna and the head of the user for blocking RF radiation, and communication interface for connecting the antenna to the transmitter, wherein, in response to the processor, the transmitter generates, via the communication interface, the antenna to emits RF radiation, and the shield prevents such radiation from penetrating there through toward the user. All the features mentioned above with respect to the antenna apparatus can be optionally employed in conjunction with the personal communication device.